Portable boring machine



Jan. 8, 1946. H. D. WRENN PORTABLE BORING MACHINE Filed March 6, 1944 Patented Jail. 8, 1946 UNITED STATES PATENT OFFICE V f 2,392,564" p PORTABLE onnier/mourns v Henry Durrer Wrenn, Gennantown, Tenn, Application March 6, 1944', Serial No. 525,242 1 1 Claim.

This invention relates to a portable boring machine, and it is particularly an object of the invention to provide a device of this kind which can be employed to advantage in the boring of cylinders and wherein the device is of a type to be attached directly to the cylinder to be bored.

It is also an object of the invention toprovide a boring machine which can be used without necessitating the removal of the cylinder to be bored and wherein the usual packing box of the cylinder is employed to assure accurate alignment of the boring shaft of the machine.

The invention consists in the details of construction and in the combination and arrangement of the several parts of my improved portable boring machine whereby certain important advantages are attained, as will be hereinafter more fully set forth.

In order that my invention may be better understood, I will now proceed to describe the same with reference to the accompanying drawing, wherein:

Figure 1 is a vertical sectional view with parts in elevation of a boring tool constructed in accordance with an embodiment of the invention and in applied position;

Figure 2 is a sectional view taken substantially on the line 2--2 of Figure 1; and

Figure 3 is a sectional view taken substantially on the line 33 of Figure 1.

In the embodiment of the invention as illustrated in the accompanying drawing, I denotes an elongated boring bar provided at its lower or working end portion with a transversely disposed opening 2 to provide a mounting for the cutting tool 3.

The inner or working end of the bar I is continued by the elongated reduced extension bar 4 which, when the machine is in use, is adapted to run through the usual packing nuts carried by the cylinder being bored, thereby assuring perfect alignment of the bar I.

The bar I is provided therealong with the keyway or groove 5 open at lxath ends and in which is received the key 6 carried by the worm gear I, whereby said worm gear I and bar I are connected for unitary rotation yet permitting endwise movement of the bar I through the worm gear I.

The worm gear I is housed within a casing 8 having its outer or top head or wall 9 removable. The lower or bottom head I 0, as herein disclosed, is fixed and is provided with a central opening I I having its inner portion defined by a surrounding rabbet I2 in which is snugly received a depending hub portion I4 carried by the worm gear I.

The removable head 9 has a central opening I5 in which is snugly received the second hub portion I6 of the worm gear Land said opening I5 is defined by an upwardly and outwardly directed elongated sleeve I! closed at its outer end, as at I8.

The end portion of the bar I within the sleeve I1 is provided with an elongated and axially disposed socket I9 having its outer end closed by afixed nut 20 through which threads an elongated ieed bar 2|. This bar H is disposed through the closed end I8 and is in swiveled connection therewith, as at 22, so that when desired the feed bar or screw 2| may be rotated to effect an endwise adjustment of the bar I independently of the endwise movement of such bar when rotated under the action of the gear 'I.

This feed bar or screw 2I, however, is normally locked against rotation by the holding screw 23 threading into the closed end portion l8 of the sleeve IT for binding action on the feed bar or screw 2|. This feed bar or screw 2I has an end portion extending outwardly beyond the closed end I8 which is adapted to be engaged by a suitable implement for eifecting the desired rotation of the feed bar or screw.

Within the casing 8 is rotatably supported a worm 24 meshing with the worm gear 'I and which worm 24 is provided with a shaft 25 extendin exteriorly of the casing 8 and adapted to be coupled with any suitable source of power.

The fixed'head or wall I0 is provided therearound with a circumferentially spaced short arm 26 herein disclosed as integral with said bottom head or wall. The outer end portions of these relatively short arms 26 in the present embodiment of the invention are also integrally formed with an annular fiat member 21 which is adapted to be placed directly upon the end flange of a cylinder or the'like to be bored after the removal of the usual head for such end of the piston. This annular member 21 is providedwith the openings 28 so positioned as to register with the usual bolt openingsin the flange of the cylinder, whereby the machine may be rigidly mounted upon the cylinder to be bored.

From the foregoing description it is thought to be obvious that a portable boring machine constructed in accordance with my invention is particularly well adapted for use by reason 01 the convenience and facility with which it may be assembled and operated,

What is claimed is:

A cylinder boring machine, comprising an annular member adapted to be mounted upon the open end of the cylinder to be bored, a gear casing having a bottom and an integral upstanding encircling side wall, said bottom having an opening centrally therethr'ough, arm members carried by said annular member and supporting said casing h ad lq i i Said casing 1 ha i g an integralaip's-tanding sleeve, a gear rotatably supg ported in's aidcasing and having a'central'opening coaxial with said first openin and with said sleeve, means for rotating said 'gear, a bar member extending through the gear opening-and-the first opening and into said sleeve, said bar having a key-way longitudinally thereof, -a=-key carried by the gear and slidably engaged-in the Iggyay,

the portion of the bar within the sleeve being tubular and open at its upper end, the opposite end portion ofthe bar being formed to provide a guide stem, said bar below the annular member being formed to carry a cutting tool, a screw secured at one end to the top of the sleeve and extending downwardly into the tubular portion of the bar, a nut threaded upon said screw and secured in the open end of the tubular portion I 

